Larousse Gastronomique was originally entirely in French, so - although it was eventually translated - I see no issue with referencing a cookbook in another language. In fact, the biggest problem with these community wiki mega-polls is superficial and/or duplicate answers, so if you can go into some detail about a book that's almost certainly not in the list already, then it will be a welcome addition.
Regarding creating another poll for baking - please don't, unless you have a much more specific question in mind. The cookbook poll was one of the first questions ever posted on the site and still exists mainly for historical purposes and also as a place to which we can steer folks who stumble in asking for recipes. However, we generally don't allow "list of X" questions anymore unless "X" is something too obscure or narrow to find hundreds of on Amazon or Google. If there's a specific aspect of baking that this book really shines at and other books don't, then feel free to ask a question around that.